Polycrates of Ephesus (/pəˈlɪkrəˌtiːz/; Greek: Πολυκράτης; fl. c. 130 – 196) was an Early Christian bishop at Ephesus. Polycrates convened a synod to establish Quartodecimanism as the official position on Easter.[1] His letter was written between 186-195 AD.[2]